Cow tipping is a pastime allegedly common in rural areas, in which participants sneak up on an upright sleeping cow and then push it over for amusement. Some variants of this urban legend state that the cow is then unable to get up.
One popular variant relies on a supposition that cows lean into a steady wind while asleep in order to keep balance. Based on this, the cow tipper lightly pushes against one side of the cow's torso, and gradually increases the force of push. The cow, while asleep, leans into the push and remains upright. Then when the cow tipper has all of their body weight on the cow, they jump to the side. The cow, still leaning into the ‘wind’, tips over in that direction.
There is no evidence, aside from mostly unreliable eyewitness reports, that any cows have ever been tipped in the purported manner. In particular, nobody has ever produced any video or other reliable photographic evidence showing that it has been done.
(Wikipedia)